select q.* from (
select
u.UserId,
cast((case when exists(select * from TblUser u where u.Disabled=1) then 1 else 0 end) as bit) as aVar,
from TblUser u
)q
where q.aVar = 1
select q.* from (
select
u.UserId,
cast((case when exists(select * from TblUser u where u.Disabled=1) then 1 else 0 end) as bit) as aVar,
from TblUser u
)q
where q.aVar = 1